Gas turbine engines generally include a compressor to pressurize inflowing air, a combustor to burn a fuel in the presence of the pressurized air, and a turbine to extract energy from the resulting combustion gases. The turbine may include multiple rotatable turbine blade arrays separated by multiple stationary vane arrays. A turbine blade array may be disposed radially inward of an annular BOAS assembly. Frequently, portions of the BOAS assembly—such as seals within the assembly—may be damaged, e.g., by oxidation erosion.